DIY Billet Lower Machining

[bksa]

Well for the past months I've been tinkering with my own billet lower build. I had absolutely zero experience and knowledge with neither CNC nor machining. Although I'd say the learning curve is VERY steep, but it was an amazing experience, and it is something that I think anyone can do.

Don't be put off my the initial invest for a setup (I say it is an investment because the learning you get significantly outweighs the cost), small home hobby cnc mill is perfectly functional for this purpose, and you can resale your machine if you don't end up using it with little loss. If you have money to buy a couple ARs, then you have the money to do this.

Today I finally reached a milestone goal which is to semi-complete an acrylic lower. Granted there are still some cuts need to be done, but I think those are minor to me and can be easily done now. Hopefully I will be able to test fire my own lower some time soon.

Of course there are Pictures =]

[ckline73]

Crazy Cool!!!!!!

[Reelemup]

What software did you use to program your cnc ?

[bksa]

sollidworks/solidcam/mach3

[Siberian64]

Now that is pretty cool...
You have inspired me...
Think I might do one out Lexan...

[jfifer]

Wow thats awesome

[spdrcr]

I thought broaching the magwell was one of the more difficult parts. What are you going to do for that?

Also how are you planning to tap the hole in the buffer tower?

[bksa]

For the magwell, it is not required for it to be broached, although it is more efficient and more clean looking. The magwell can be drilled and milled so the corners are round instead of square. There are a few 80% lower manufactures that use this method to produce perfectly functional lowers.

For the buffer tube, I will use the CNC to tap the thread or buy a big tap in the exact size. Buying an already made tap would be easier.

[Vetteodyssey]

So that I can start the conversation with my wife about my new 'educational expense'. What did it cost you to get set up?

[bksa]

If you're looking for ready made CNC mills then it'll be about 2K

If you're looking to buy a manual mill and install a CNC kit, would be about 1500.

I run a conversion.

[yari]

You need some led lights on that thing. Safe it glows.. ? Fire it glows red?

[NorCalMik]

If you're looking for ready made CNC mills then it'll be about 2K

If you're looking to buy a manual mill and install a CNC kit, would be about 1500.

I run a conversion.

Mind providing details on both these options?

[Zartan]

Sweet! Ready for polish!

[vwynn]

ive been trying to learn how to machine but still having difficulties using mastercam x5.. since well iono how to use it LOL.

i cant seem to figure out how to 3d mill...

[SigUser]

hmmm.... I know that polymers and plastics are all the rage now... but how does the lowers handle the punishment of use? do the lowers crack if dropped? saw a guy the other day drop his ar10 onto the concrete floor at the gun range, nothing happened, he just picked it up... NOW will an acrylic or polymer gun crack if dropped from a height of 4-5 feet to the ground? or if I ran out of bullets and wanted to use my rifle as a bat, will the multiple swings that contact a solid surface or object make my rifle break in half like a toothpick? a weapon is meant to withstand some sort of abuse, just wondering if you guys tested anything out yet.